Ahmed Abrahim Dawed, Hiko Adem, Belina Dinaol, Gebremeskel Haben Fesseha, Kebede Isayas Asefa
Eastern Branch, Ethiopian Agriculture Authority, Dire Dawa, Ethiopia.
College of Veterinary Medicine, Haramaya University, P. O. Box 138, Dire Dawa, Ethiopia.
BMC Microbiol. 2024 Aug 1;24(1):284. doi: 10.1186/s12866-024-03439-6.
The safety of milk production in terms of foodborne infections is a worldwide issue, particularly in developing countries where production is often unhygienic. A cross-sectional study was conducted from December 2018 to August 2019 in the Meta District of Eastern Hararghe Zone, Oromia Regional State, Ethiopia. We aim to assess milk hygiene practices among smallholder dairy farmers, estimate the prevalence of Staphylococcus aureus in raw cow milk and swabs, assess associated risk factors, and the antimicrobial susceptibility test of S. aureus isolates. Face-to-face interviews with 30 respondents randomly selected from smallholder dairy farmers were used to assess the potential risk factors for S. aureus contaminations in milk. A total of 177 samples were examined using standard microbiological testing. The disc diffusion technique was also employed to assess the antibiotic susceptibility of the isolates. The data was analyzed using STATA version 14.0 statistical software.
According to the milk hygiene assessment, 80% of respondents did not wash cow udder before milking, did not use detergent to clean milk containers, and did not keep milk refrigerated before consumption or sale, while 63.3% of milk consumers ingested raw milk. They had never heard of staphylococci foodborne disease. Likewise, the overall prevalence of S. aureus was 12.42% (95%CI: 8.32-18.98). The prevalence of S. aureus in udder milk, equipment swabs, and milkers' hands was 18.8%, 26.7%, and 30%, respectively. The prevalence of S. aureus in milk is significantly associated with age, and mastitis history (p < 0.05). Moreover, old and mastitis positive animals were eight (OR: 8.40; 95%CI: 1.68-41.89) and four (OR: 4.33; 95%CI: 1.37-13.66) times more likely to be infected by S. aureus than adult, and mastitis negative animal. The isolates were resistant to penicillin G (97.4%) and tetracycline (69.2%) whereas susceptible to kanamycin, streptomycin, vancomycin, and cefotaxime, at 84.6%, 71.8%, 64%, and 58.8%, respectively.
This study revealed the presence of antimicrobial-resistant patterns of S. aureus on commonly used antibiotics, as well as inadequate milk handling practices in the study area. Thus, awareness should be created on proper milk handling and hygiene as well as appropriate uses of antibiotics should be encouraged.
从食源性感染角度来看，牛奶生产安全是一个全球性问题，在生产往往不卫生的发展中国家尤为如此。2018年12月至2019年8月在埃塞俄比亚奥罗米亚州东部哈拉尔格地区的梅塔区进行了一项横断面研究。我们旨在评估小农户奶农的牛奶卫生习惯，估计生牛奶和拭子中金黄色葡萄球菌的流行率，评估相关风险因素以及金黄色葡萄球菌分离株的抗菌药敏试验。通过对从小农户奶农中随机选取的30名受访者进行面对面访谈，以评估牛奶中金黄色葡萄球菌污染的潜在风险因素。使用标准微生物检测方法共检测了177个样本。还采用纸片扩散法评估分离株的抗生素敏感性。使用STATA 14.0统计软件对数据进行分析。
根据牛奶卫生评估，80%的受访者在挤奶前不清洗奶牛乳房，不使用洗涤剂清洁牛奶容器，在食用或销售前不冷藏牛奶，而63.3%的牛奶消费者饮用生牛奶。他们从未听说过葡萄球菌食源性疾病。同样，金黄色葡萄球菌的总体流行率为12.42%（95%置信区间：8.32 - 18.98）。乳房牛奶、设备拭子和挤奶工手部金黄色葡萄球菌的流行率分别为18.8%、26.7%和30%。牛奶中金黄色葡萄球菌的流行率与年龄和乳腺炎病史显著相关（p < 0.05）。此外，年老且患有乳腺炎的动物感染金黄色葡萄球菌的可能性分别是成年且无乳腺炎动物的8倍（比值比：8.40；95%置信区间：1.68 - 41.89）和4倍（比值比：4.33；95%置信区间：1.37 - 13.66）。分离株对青霉素G（97.4%）和四环素（69.2%）耐药，而对卡那霉素、链霉素、万古霉素和头孢噻肟敏感，敏感率分别为84.6%、71.8%、64%和58.8%。
本研究揭示了金黄色葡萄球菌对常用抗生素存在耐药模式，以及研究区域内牛奶处理方式不当的情况。因此，应提高对正确牛奶处理和卫生的认识，并鼓励合理使用抗生素。
